1. Technical Field
The present invention generally relates to a resistless lithography method for fabricating fine structures and, in particular, to a resistless lithography method for fabricating sub 100 nm structures in a carrier material or semiconductor material.
2. Related Art
In the development of lithography methods for fabricating fine structures in a sub 100 nm regime, problems may arise from a resist chemistry, the mask fabrication, and the complexity of the lithography system.
A type of lithography referred to as 157 nm lithography has been reached in the further development of optical lithography for fabricating fine structures in a regime smaller than 100 nm. These lithography methods use novel resist materials. However, the existing materials may not satisfy technical requirements with regard to such small structures. These new materials may use new mask fabrication methods and their development may be cost intensive and difficult to handle.
As an alternative to conventional optical lithography methods, a maskless lithography method, (e.g. an electron beam direct write lithography (EBDW)), has been introduced where a suitable resist may be required. A resist may be an organic exposure layer including a polymer.
Other alternatives to exposure are, for example, ion projection lithography (IPL) methods, so called stencil masks being used to image the structures on a special resist material. However, the fabrication of a suitable resist material, in particular, is increasingly restricting the realization of structures that are becoming ever finer.